Method for preparing potassium fluoride

Abstract

The invention relates to a method for preparing potassium fluoride, which takes ammonium fluoride and potassium hydroxide as main raw materials and concretely comprises the steps as follows: (1) an ammonium fluoride solution is injected into a reaction kettle which then starts to stir, the potassium hydroxide is added in uniform speed, and the pH value is 7.5 to 8.0 at a reaction end point; (2) after the reaction in the reaction kettle is complete, liquid flows into a concentration tank automatically; (3) a potassium fluoride solution which is concentrated is injected into a transferring tank and then is injected into a spray drying tower for drying from the transferring tank; (4) water vapor and fine dust are dried and processed through cyclone separation and cooling for gas-liquid separation; the liquid enters into a receiving tank, and the gas is processed through secondary absorption; the absorbed liquid enters in the receiving tank, and water vapor is evacuated. Because fluosilicic acid is a by-product of a phosphate fertilizer factory, the cost is lower and the material is easy to get, thereby greatly lowering the manufacturing cost of the potassium fluoride. Ammonia gas which is generated during the reaction process in the method is recycled through a closed cycle completely, so the environmental protection pressure is reduced and the manufacturing cost is lowered to a certain extent. The method has good social benefit, economic benefit and environmental protection benefit, and is easy to be popularized and applied.

Description

technical field [0001] The invention relates to a method for preparing potassium fluoride, in particular to a method for preparing potassium fluoride with ammonium fluoride and potassium hydroxide as main raw materials. Background technique [0002] Potassium fluoride has a wide range of uses, mainly used as a welding flux for various metals and alloys; it is widely used as a fluorinating agent in the production of organic compounds; it is used in the production of sodium fluoroacetate and fluoroacetamide pesticides in pesticides; it is used in medicine to make norfloxacin; in addition, it can be used as an absorbent (absorbing HF and moisture), and is also a raw material for the preparation of potassium bifluoride, and can also be used for glass carving and food preservation. [0003] The related industries that use potassium fluoride have a stable scale and a stable demand for potassium fluoride. Especially since the beginning of this century, with the rapid development of...

AI Technical Summary

Problems solved by technology

The traditional method of producing potassium fluoride mostly uses potassium carbonate or potassium hydroxide - hydrofluoric acid method. Hydrofluoric acid is mainly produced by the reaction of fluorite and sulfuric acid. The traditional process needs to consume a valuable strategic resource - fluorite. Now the country Increase the control of fluorite, the price of fluorite is getting higher and higher, and the price of hydrofluoric acid will also increase accordingly, which affects the production cost of potassium fluoride. Therefore, it is necessary to find a new source of fluorine to replace hydrogen fluoride Acid is an important way to reduce the cost of potassium fluoride and improve the competitiveness of potassium fluoride

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